Method for operating a user terminal of an agricultural machine and agricultural machine

ABSTRACT

The disclosure refers to a method for operating an user terminal (7) of an agricultural machine, comprising: providing a user terminal (7) in a control system (3) of an agricultural machine, the user terminal (7) connected to a power supply (13) and configured to transmit, through a control bus (6), control signals to functional elements (10a; 10b) of the agricultural machine; applying a supply power, through a supply line, to the user terminal (7) with a voltage level provided by the power supply (13), the voltage level being an normal operation voltage level; determining at least one of a turn-on state of an ignition device of the agricultural machine and a drop of the supply power provided by the power supply (13) in the supply line to a reduced voltage level which is smaller than a minimum operation voltage level, the minimum operation voltage level being equal to or smaller than the normal operation voltage level and the drop of the supply power being caused by the ignition device switching into the turn-on state; in response to the determining, boosting the reduced voltage level to a boosted voltage level by a voltage upscaling device, the boosted voltage level reaching at least the minimum operation voltage level; operating, while the ignition device is in the turn-on state, the user terminal (7) with the power supply having the boosted voltage level; determining at least one of a turn-off state of the ignition device and termination of the drop of the supply power provided by the power supply (13) in the supply line; in response to the determining, terminating the boosting of the reduced voltage level; and applying the supply power to the user terminal (7) with the voltage level provided by the power supply (13), the voltage level being the normal operation voltage level. Further, an agricultural machine is provided.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a 35 U.S.C. 371 National Stage Patent Application ofInternational Application No. PCT/EP2018/070288, filed Jul. 26, 2018,which claims priority to European application 17184323.8, filed Aug. 1,2017, each of which is hereby incorporated by reference in its entirety.

BACKGROUND

User terminals are provided as a user interface for receiving user inputfor controlling operation of functional elements of an agriculturalmachine. For example, in an agricultural machine comprising a tractorand an implement trailed by or carried on the tractor the user terminalmay be located in the tractor. The user terminal is provided withhardware and software components including, for example, atouch-sensitive display, and additional input devices such as arotatable control knob or a joystick. The user terminal is connected toa control system of the agricultural machine. In response to receivinguser input through the user terminal, control signals are generated forcontrolling operation of functional elements of the tractor and/or theimplement, the functional elements being connected to a control bus usedfor transmitting the control signals to the functional components. Alocal control unit may be assigned to one or more of the functionalelements, the local control unit being connected to the data bus forcontrol signals transmission.

After ignition of the engine of the agricultural machine, there is abooting process for starting the user terminal and enabling a mode ofoperation for the user terminal which allows for receiving user input.

Document U.S. Pat. No. 5,897,600 A discloses a modular control systemfor controlling a mobile material distribution apparatus. The modularcontrol system is adaptable for use with any of a plurality ofdistribution apparatus. It includes a control module for controlling thedistribution apparatus and a user console for communicating with a user.The control module and user console are coupled via a data link.

Document US 2014/0278022 A1 discloses a power supply device which ismounted in a vehicle capable of starting an engine with power suppliedfrom a battery. The power supply includes a booster configured to boostvoltage supplied from the battery, a detecting unit configured to detectan engine start, a counting unit configured to count an engine startcount based on the detecting unit, and a control unit configured tocontrol the booster. The control unit outputs a control signal to permitthe booster to boost the voltage in response to the engine start whenthe engine start count counted by the counting unit within a timerperiod does not exceed an allowable number of times.

Document US 2012/0173038 A1 discloses a vehicle mount computer having aconfigurable behavior controlled by a vehicle's ignition switch. A usercan configure the computer to perform an action, switch modes, orexecute a software application in response to the ignition switch beingpressed or the position of the ignition switch being adjusted. Forexample, the computer can be configured to switch to a standby mode orhibernation mode, shutdown, prompt the user to select an action, or donothing in response to the ignition switch being placed in an offposition. The ignition switch can be electrically coupled to an input ofthe computer so that the computer's operating system or anotherapplication can monitor the status of the ignition switch. The operatingsystem or application can cause the computer to perform the configuredresponse upon detecting a change in the ignition switch's position or anactuation of the ignition switch.

SUMMARY

It is an object of the present disclosure to provide a method foroperating a user terminal of an agricultural machine and an agriculturalmachine which allows for improved operation of the user terminaldepending on the different use scenarios in field operation.

For solving the problem, preferred embodiments of a method for operatinga user terminal of an agricultural machine and an agricultural machineare disclosed.

According to an aspect, a method for operating a user terminal of anagricultural machine is provided. The method comprises: providing a userterminal in a control system of an agricultural machine, the userterminal connected to a power supply and configured to transmit, througha control bus, control signals to functional elements of theagricultural machine; applying a supply power, through a supply line, tothe user terminal with a voltage level provided by the power supply, thevoltage level being an normal operation voltage level; determining atleast one of a turn-on state of an ignition device of the agriculturalmachine and a drop of the supply power provided by the power supply inthe supply line to a reduced voltage level which is smaller than aminimum operation voltage level, the minimum operation voltage levelbeing equal to or smaller than the normal operation voltage level andthe drop of the supply power being caused by the ignition deviceswitching into the turn-on state; in response to the determining,boosting the reduced voltage level to a boosted voltage level by avoltage upscaling device connected to the supply line, the boostedvoltage level reaching at least the minimum operation voltage level;operating, while the ignition device is in the turn-on state, the userterminal with the power supply having the boosted voltage level;determining at least one of a turn-off state of the ignition device andtermination of the drop of the supply power provided by the power supplyin the supply line, the termination of the drop being caused by theignition device switching into the turn-off state; in response to thedetermining, terminating the boosting of the reduced voltage level; andapplying the supply power, through the supply line, to the user terminalwith the voltage level provided by the power supply, the voltage levelbeing the normal operation voltage level.

According to further aspect, an agricultural machine is provided,comprises a control system; a user terminal provided in the controlsystem; a power supply connected to the user terminal through a supplyline; a voltage upscaling device connected to the supply line;functional control elements; and a control bus provided in the controlsystem and configured to transmit control signals from the user terminalto the functional elements. The user control system is configured tooperate the user terminal according to the above method.

The operating of the user terminal may comprise: enabling a user controlmode of operation of the user terminal; running software applications inthe user terminal; enabling a display device of the user terminal; andenabling the control bus, thereby, operating the control bus in a buscontrol mode allowing for transmission of the control signals throughthe control bus. The enabling of the user control mode of operation maybe applied while the ignition device is in the turn-on state and whilethe reduced voltage level is boosted to the boosted voltage level. Also,the enabling of the user control mode may be applied while the ignitiondevice is in the turn-off state, the voltage level supplied being thenormal operation voltage level.

The operating of the user terminal may comprise controlling operation ofone of the functional elements of the agricultural machine in the usercontrol mode of operation. The controlling may comprise: receiving auser input for controlling operation of the one of the functionalelements through an input device of the user terminal; in response tothe user input, generating present control signals; transmitting thepresent control signals to the control unit assigned to the one of thefunctional elements through the control bus; and operating thefunctional elements according to the present control signals.

The operating of the user terminal may comprise enabling a standby modeof operation for the user terminal. The enabling may comprise:continuing with running one or all of the software applications in theuser terminal; disabling the display device of the user terminal; anddisabling the control bus, thereby, preventing transmission of thecontrol signals from the user terminal through the control bus. Theenabling of the standby mode of operation may be applied while theignition device is in the turn-on and the reduced voltage level isboosted to the boosted voltage level. Also, the enabling of the standbymode of operation may be applied while the ignition device is in theturn-off state.

The operating of the user terminal may comprise disabling the controlmode of operation and enabling the standby mode of operation for theuser terminal in response to the determining of the turn-off state.

The operating the user terminal may comprise, while the ignition deviceis in the turn-on state, re-enabling the control mode of operation forthe user terminal.

The method may further comprise preventing the user terminal, while theignition device is in the turn-on state, from at least one of switchingto a turn-off state and re-booting.

Further, the method may comprise providing the voltage upscaling devicein the user terminal.

In the method, the boosting may comprise boosting a reduced voltagelevel of about 2 to 4 V to a boosted voltage level of about 10 to 12 V.In general, in the different embodiments DC voltage may be upscaled.

The providing may comprise providing the user terminal in a tractor ofthe agricultural machine, the tractor trailing or carrying an implement,wherein at least some of the functional elements are provided on theimplement.

In an alternative embodiment, a method for operating a user terminal ofan agricultural machine may be provided. The method comprises providinga user terminal in a control system of an agricultural machine, the userterminal connected to a power supply and, through a control busconfigured to transmit control signals, to the functional elements ofthe agricultural machine; and enabling operation of the user terminal,after a period of time the user terminal was turned-off before. Theenabling of the operation of the user terminal is comprising thefollowing: enabling a user control mode for operation of the userterminal; running software applications in the user terminal; enabling adisplay device of the user terminal; and enabling the control bus,thereby, operating the control bus in a bus control mode allowing fortransmission of the control signals through the control bus. Theoperation of one of the functional elements of the agricultural machineis controlled in the user control mode of operation, the controllingcomprising the following: receiving a user input for controllingoperation of the one of the functional elements through an input deviceof the user terminal; in response to the user input, generating presentcontrol signals; transmitting the present control signals to the controlunit assigned to the one of the functional elements through the controlbus; and operating the functional elements according to the presentcontrol signals. The user control mode of operation is disabled, and astandby mode of operation for the user terminal is enabled, suchenabling comprising: continuing with running one or all of the softwareapplications in the user terminal; disabling the display device of theuser terminal; and disabling the control bus, thereby, preventingtransmission of the control signals from the user terminal through thecontrol bus. Following, the control mode of operation is re-enabled forthe user terminal.

According to further aspect, an agricultural machine is provided,comprising a control system, a user terminal provided in the controlsystem and connected to a power supply, functional control elements, anda control bus provided in the control system and configured to transmitcontrol signals from the user terminal to the functional elements,wherein the user control system is configured to operate the userterminal according to the above method.

Having the different modes of operation for the user terminalimplemented will allow for improved operation of the control system ofthe agricultural machine, specifically with regard to the user terminal.Depending on a present working scenario, the ignition device of theagricultural machine may be turned on or off. During operation of theagricultural machine on the field, there may be switching between theturning on and turning off state of the ignition device. In case ofdetermining the turn-off state of the ignition device, the standby modeof operation is enabled for the user terminal, the standby mode ofoperation providing reduced or limited functionality compared to thecontrol mode of operation. However, there are one or more softwareapplications in the user terminal still running in the standby mode. Forreturning to the control mode of operation, this will allow for easierre-activation of the additional functionality of the user terminal shutoff in the standby mode.

Depending on the present use scenario for the agricultural machine thereis switching between the control mode of operation and the standby modeof operation.

The method may further comprise: determining a turn-on state of anignition device of the agricultural machine in the control system;enabling operation of the user terminal within a starting time afterdetermining the turn-on state; determining a turn-off state of theignition device of the agricultural machine; and in response to thedetermining of the turn-off state, disabling the control mode ofoperation and enabling the standby mode of operation for the userterminal.

The enabling of operation may comprise enabling of the operation of theuser terminal within a starting period of time after determining theturn-on state, and the re-enabling of the control mode of operation maycomprise re-enabling the control mode of operation for the user terminalwithin a re-starting period of time after determining a re-turn-on stateof the ignition device, the re-starting period of time being shorterthan the starting period of time.

The re-starting period of time may be shorter than the starting periodof time by at least 70%. In an alternative embodiment, the re-startingperiod of time may be shorter than the starting period of time by atleast about 80%.

The enabling of the standby mode of operation for the user terminal maycomprise disabling an input device of the user terminal. For example, atleast one of a touch sensitive input device provided on the display ofthe user terminal and an external input device may be disabled, thereby,preventing user input.

The disabling of the control bus may comprise, within an OSI (OpenSystem Interconnection) layer model of the control bus, disablingcontrol signal or message transmission from a data link layer to aphysical layer. The control bus may be provided as a CAN bus (ControllerArea Network protocol). In an embodiment, the control bus, according tothe OSI model, may be implemented with the physical layer, the data linklayer, and an application layer. The physical layer may provide forbasic hardware required for a control bus network, such as a CAN busnetwork, i.e. the ISO 11898 electrical specification. The data linklayer may be responsible for transferring messages/signals from a nodeto the network (without errors). The application layer may provide forupper-level communication functions of the OSI layer model. In general,although the other layers may be implemented by software and/orhardware, the physical layer is implemented by hardware. In the standbymode of operation for the user terminal, by the disabling control signaltransmission from the user terminal to one of the functional elements isprevented. Specifically, the user is prevented from control input.Signal transmission between the functional elements through the controlbus may still be enabled. In such alternative embodiments, nodes of thecontrol system connected to the control bus other than the user terminalmay be provided with the signal transmission functionality of thecontrol bus.

The disabling of the display may comprise one of outputting a standbyscreen on the display device of the user terminal, and turning-off abacklight illumination of the display device of the user terminal. Thestandby screen may be a black image presented on the display device. Thedisplay device may be provided with a liquid crystal display. In thestandby mode of operation any (further) updating of content displayed onthe display device may be prevented.

In the standby mode of operation, the method may further comprise:determining a standby time in the control system, the standby timeindicating a period of time lapsed after the enabling of the standbymode of operation for the user terminal; determining that the standbytime is exceeding a standby time limit; and, in response to thedetermining, turning-off the user terminal. The standby time limit, forexample, may be about 12 h.

The providing may comprise providing the user terminal in a tractor ofthe agricultural machine, the tractor trailing or carrying an implement,wherein at least some of the functional elements are provided on theimplement. The implement may be selected, for example, from thefollowing group: loader wagon, sprayer, baler, rake, and mower.

With regard to the agricultural machines, the alternative embodimentsdescribed above for the methods for operating may apply mutatismutandis.

Each of the functional elements may be assigned an electronic controlunit which is connected to the data or control bus for receiving (and/orsending) electronic signals such as control signals. A single electroniccontrol unit may be assigned to more than one functional element. Theelectronic control units each may provide for a node connected to thecontrol bus.

DESCRIPTION OF EMBODIMENTS

Following, further embodiments are described in detail with reference tofigures. In the figures, show:

FIG. 1 a schematic representation of a control system of an agriculturalmachine or system provided with a tractor and an implement trailed by orcarried on the tractor;

FIG. 2 a schematic representation for the operation of a user terminalin the control system;

FIG. 3 a schematic representation of functional elements of the userterminal;

FIG. 4 a schematic representation of elements of a control bus providedin the control system;

FIG. 5 a schematic representation of the time course of operation of theuser terminal; and

FIG. 6 a schematic representation of a control system of an agriculturalmachine or system provided with a tractor and an implement trailed by orcarried on the tractor, wherein the power supply is provided with afunctional device for voltage upscaling.

FIG. 1 shows a schematic representation of an agricultural machine orsystem having a tractor 1 and an implement 2 trailed by or carried onthe tractor 1.

An agricultural machine control network 3 provides for an electroniccontrol system of the agricultural machine or system. The agriculturalmachine control network 3 comprises a tractor control network 4 and animplement control network 5. The agricultural machine control network 3is having a data or control bus 6 to which, according to the embodimentshown, a user control terminal 7, a task controller 8, and a pluralityof electronic control units 9 are connected. Each of the electroniccontrol units 9 is assigned to a functional element 10 a, 10 b providedin the tractor 1 and the implement 2, respectively. In an alternativeembodiment, the electronic control units 9 connected to the user controlterminal 7 through the data bus 6 may only be applied to the functionalelement(s) 10 b of the implement 2, but not to the functional element(s)10 a of the tractor 1.

With regard to the implement 2, the functional elements 10 b may also bereferred to as working unit. Through the data bus 6 electronic data,such as control signals, may be transmitted between the components,units, modules or elements connected to the data bus 6. The electroniccontrol system of the agricultural machine control network 3 mayimplement the ISO 11783 standard, preferably the ISO 11783-11 standard.

The data bus 6 may be implemented with a Controller Area Network (CANbus) which is a multi-master serial bus standard for connectingElectronic Control Units (ECUs) also known as nodes. Each ECU isassigned to at least one of the functional elements 10 a, 10 b. Two ormore nodes are required on the CAN network to communicate. Thecomplexity of the node can range from a simple I/O device up to anembedded computer with a CAN interface and sophisticated software. Thenode may also be a gateway allowing a standard computer to communicateover a USB or Ethernet port to the devices on a CAN network. All nodesmay be connected to each other through a two wire bus. The wires may be120Ω nominal twisted pair. ISO 11898-2, also called high speed CAN, usesa linear bus terminated at each end with 120Ω resistors.

The data bus 6 is provided with a plug connector 11 connecting thetractor control network 4 and the implement control network 5.

The user or operator control terminal 7 is provided with a terminaldisplay 12 which may comprise a touch sensitive display and provides foruser control and user display. Further, the user control terminal 7 isprovided with a processor unit comprising a processor and a memoryelement connected to the processor. Multiple software applicationsimplemented on the user control terminal 7 may be runningsimultaneously.

Through the user control terminal 7 user input may be received forcontrolling the functional elements 10 a, 10 b of the agriculturalmachine or system. Also, through the terminal display 12 operationinformation may be displayed to the user.

A battery 13 is provided for power supply, for example, to the usercontrol terminal 7. In general, the power provided by the battery and/orsome other power supply source may be supplied to the components of theagricultural machine in need for any power supply during operation by aso-called central electronic unit (CEU) as it is known as such.

FIG. 2 shows a schematic representation for operating the user controlterminal 7. The mode of operation of the user control terminal 7 willdepend on the state of an ignition device of the agricultural machine,specifically an ignition device of the tractor 1. The state of theignition device, specifically a turn-on state and a turn-off state, willbe determined by the agricultural machine control network 3.

The user control terminal 7 comprises hardware and software componentseach of which is assigned a hardware startup 20 and a software startup21, respectively. If a turn-on state of the ignition device of theagricultural machine is determined (step 30), as part of a bootingprocess, the hardware startup 20 is initiated which in turn will startthe software startup 21 in step 31. Thereby, a control mode of operation(idle state or mode 22) is finally implemented for the user controlterminal 7 (step 32).

The period of time between the turn-on of the ignition device and theenabling of the control mode of operation for the user control terminal7 may be referred to starting time after the determining of the turn-onstate for the ignition device. In the control mode of operation one ormore software applications are running in the user control terminal 7.Also, the data bus 6 is enabled, thereby, operating the date bus 6 inbus control mode allowing for transmission of control signals throughthe data bus 6 to the functional elements 10 a, 10 b of the agriculturalmachine. A driving circuit configured to drive terminal elements of theuser control terminal 7 is provided with a normal operation power.

If in step 33 a turn-off state is detected for the ignition device, astandby mode of operation 23 is implemented for the user controlterminal 7, wherein the standby mode of operation 23 is implementedafter the user control terminal 7 has been in the idle state or process22 (control mode) before. In the standby mode of operation 23 the usercontrol terminal 7 is provided with limited or reduced functionality. Inan embodiment, in the standby mode of operation 23 the illumination ofthe terminal display 12 of the user control terminal 7 is turned off.For example, a backlight illumination of a liquid crystal display (LCD)device may be turned off. The enabling of the standby mode of operationfor the user terminal 7 may comprise disabling an input device of theuser terminal. For example, at least one of a touch sensitive inputdevice provided on the terminal display 12 of the user terminal 7 and anexternal input device may be disabled, thereby, preventing user input.

Also, the data bus 6 is disabled, thereby, preventing transmission ofcontrol signals through the data bus 6 to the functional elements 10 a,10 b. Referring to FIG. 3, the disabling of the control bus 6 maycomprise, within an OSI (Open System Interconnection) layer model 40 ofthe control bus 6, disabling control signal or message transmissionbetween a physical layer 41 and a data link layer 42. The control bus 6may be provided as a CAN bus (Controller Area Network protocol). In theexample embodiment shown, the control bus 6, according to the OSI model40, may be implemented with the physical layer 41, data link layer 42,and an application layer 43. The physical layer 41 may provide for basichardware required for a control bus network, such as a CAN bus network,i.e. the ISO 11898 electrical specification. The data link layer 42 maybe responsible for transferring messages/signals from a node to thenetwork (without errors), such nodes comprising, for example, the usercontrol terminal 7 and the ECUs assigned to at least one of thefunctional elements 10 a, 10 b. The application layer 43 may provide forupper-level communication functions of the OSI layer model 40. Ingeneral, although the other layers such as the data link layer 42 andthe application layer 43 may be implemented by software and/or hardware,the physical layer 41 is implemented by hardware.

In the standby mode of operation for the user control terminal 7, by thedisabling control signal transmission from the user control terminal 7to one of the functional elements 10 a, 10 b is prevented. Specifically,the user is prevented from control input. Signal transmission betweenthe functional elements 10 a, 10 b through the data bus 6 may still beenabled. In such alternative embodiments, nodes of the control system 3connected to the data bus 6 other than the user control terminal 7 maybe provided with the signal transmission functionality of the data bus6.

Referring to FIG. 3, the physical 41, the data link layer 42, and theapplication layer 43 compare to a physical layer 50, and anobject/transfer layer 51 in the CAN bus model (ISO 11898).

In the user control terminal 7 providing a node in the CAN bus network,software application 60, 61, 62 are implemented, such softwareapplication 60, 61, 62 being functionally connected to a socket CAN 63(virtual CAN bus implemented by software). The socket CAN 63 isconnected to CAN bus hardware 64 via a connection 65. Such connection 65is disabled in the standby mode of operation of the user controlterminal 7. For disabling, for example, software switches provided withhardware drivers may be switched off.

In the standby mode of operation 23, one or all of the softwareapplications 60, 61, 62 implemented in the user control terminal 7 maycontinue to be running. For example, a task controller (e.g. ISO11783-14) implemented as one of the software application may be keptrunning in the standby mode of operation. In addition or as analternative, a virtual terminal also referred to as universal terminal(e.g. ISO 11783-6) may continue to run as a software application in theuser control terminal 7 in the standby mode.

If in step 34 it is determined that the ignition device is turned on,the user control terminal 7 will return to the control mode ofoperation, thereby, enabling the idle state or process 22 (control modeof operation).

If it is determined that the user control terminal 7 has been operatedin the standby mode of operation 23 longer than a standby time limit,which for example may be set to about 12 h, there is a shutdown 24 (step35) which will require a reset 25 for re-starting (step 36).

In case of failure detection, the reset 25 may be started form the idlestate 22 or the standby state 24 (step 37).

Table 1 provides summarized information on the operation of the usercontrol terminal 7. The status of different elements of the user controlterminal 7 depending on the state of operation is indicated.Specifically, reference is made to the screen of the terminal display12, user input elements “Button”, and backlight illumination “LEDs”.

TABLE 1 State Power Screen Buttons LEDs Description Hardware Startup Offn/a n/a n/a Hardware initialization, no (after user control stateguarantees terminal was tuned off) Software Startup Off On On On Duringterminal startup Idle (control mode) On On On On Control mode ofoperation Standby mode On Off Off Off With ignition turned off (standbymode of operation) Shutdown (user control On Previous/ On On Duringterminal shutdown terminal turned off) black Reset Off Off On On Betweenterminal shutdown and startup

The level of voltage power applied in the control mode and the standbymode, respectively, will be different.

FIG. 4 shows a schematic representation with regard to the mode ofoperation of the user control terminal 7 in dependence on the state ofthe ignition device. For example, “0” indicates for the ignition statethat the ignition device is turned off. Contrary, “1” indicates that theignition device is turned on. After the standby time limit of 12 h haslapsed, the user control terminal 7 is turned off. Thereby, the usercontrol terminal 7 is returning to the turned-off state from which it isstarted according to the schematic representation in FIG. 3.

With regard to the operation of the agricultural machine control network3, as an alternative or in addition to the operation of the user controlterminal 7 in the different modes of operation, a voltage or powercontrol mechanism may be applied. If the ignition device of theagricultural machine is turned on for starting an engine, a power levelat which power is provided by the battery 13 will drop. For example, ifa normal power or voltage level of about 12 V is provided, it may dropto about 2 to 3 V for the time of starting the engine by activating theignition device.

According to the embodiment shown in FIG. 5, a functional circuit 70 isprovided which will upscale or boost the power level to the normalvoltage level. Such upscaling will be limited to the time period theignition device is activated. Specifically, the upscaled voltage (whichis about the normal voltage level) will be provided to the user controlterminal 7, thereby, preventing the power or voltage level applied tothe user control terminal 7 to drop below a level which would cause are-booting of the user control terminal 7. Functional circuit devicesconfigured to upscale or boost voltage level are known as such withdifferent hardware/software design. By the boosted voltage, for example,the standby mode of operation may be kept for the user control terminal7, thereby, preventing completely restarting the user control terminal 7by booting. Rather, the user control terminal 7 can switch from thestandby mode of operation into the control mode of operation (directly)without re-booting caused by the voltage drop due to activation of theignition device.

FIG. 6 shows a schematic representation of an example for operation ofthe power supply which uses the functional circuit 70 for voltageboosting or upscaling. The voltage output of the functional circuit 70,according to the embodiment shown, is applied to the user controlterminal 7, but, in addition or as an alternative, may also be appliedto other components of the agricultural machine.

If the power level provided by the battery 13 is higher than a requirednormal operation level, the functional circuit may be configured tostill output voltage having the required normal operation level.

In an embodiment, the functional circuit 70 may be provided in the usercontrol terminal 7 schematically indicated by the dashed line in FIG. 6.

The features disclosed in this specification, the figures and/or theclaims may be material for the realization of various embodiments, takenin isolation or in various combinations thereof.

The invention claimed is:
 1. Method for operating a user terminal (7) ofan agricultural machine, comprising providing the user terminal (7) in acontrol system (3) of the agricultural machine, the user terminal (7)connected to a power supply (13) and configured to transmit, through acontrol bus (6), control signals to functional elements (10 a; 10 b) ofthe agricultural machine; applying a supply power, through a supplyline, to the user terminal (7) with a voltage level provided by thepower supply (13), the voltage level being a normal operation voltagelevel; determining at least one of a turn-on state of an ignition deviceof the agricultural machine and a drop of the supply power provided bythe power supply (13) in the supply line to a reduced voltage levelwhich is smaller than a minimum operation voltage level, the minimumoperation voltage level being equal to or smaller than the normaloperation voltage level and the drop of the supply power being caused bythe ignition device switching into the turn-on state; in response to thedetermining at least one of a turn-on state, boosting the reducedvoltage level to a boosted voltage level by a voltage upscaling deviceconnected to the supply line, the boosted voltage level reaching atleast the minimum operation voltage level; operating, while the ignitiondevice is in the turn-on state, the user terminal (7) with the powersupply having the boosted voltage level by enabling a standby mode ofoperation for the user terminal (7), by: continuing with running one orall of the software applications in the user terminal (7); disabling thedisplay device of the user terminal (7); and disabling the control bus(6), thereby, preventing transmission of the control signals from theuser terminal (7) through the control bus (6); determining at least oneof a turn-off state of the ignition device and termination of the dropof the supply power provided by the power supply (13) in the supplyline, the termination of the drop being caused by the ignition deviceswitching into the turn-off state; in response to the determining atleast one of a turn-off state, terminating the boosting of the reducedvoltage level; and applying the supply power, through the supply line,to the user terminal (7) with the voltage level provided by the powersupply (13), the voltage level being the normal operation voltage level.2. Method of claim 1, wherein the operating of the user terminal (7)comprises enabling a user control mode of operation of the user terminal(7); running software applications in the user terminal (7); enabling adisplay device of the user terminal (7); and enabling the control bus(6), thereby, operating the control bus (6) in a bus control modeallowing for transmission of the control signals through the control bus(6).
 3. Method of claim 2, wherein the operating of the user terminal(7) comprises controlling operation of one of the functional elements(10 a; 10 b) of the agricultural machine in the user control mode ofoperation, comprising receiving a user input for controlling operationof the one of the functional elements (10 a; 10 b) through an inputdevice of the user terminal (7); in response to the user input,generating present control signals; transmitting the present controlsignals to the control unit assigned to the one of the functionalelements (10 a; 10 b) through the control bus (6); and operating thefunctional elements (10 a; 10 b) according to the present controlsignals.
 4. Method of claim 1, wherein the operating of the userterminal (7) comprises disabling the control mode of operation andenabling the standby mode of operation for the user terminal (7) inresponse to the determining of the turn-off state.
 5. Method of claim 1,wherein the operating the user terminal (7), while the ignition deviceis in the turn-on state, comprises re-enabling the control mode ofoperation for the user terminal (7).
 6. Method of claim 1, furthercomprising preventing the user terminal (7), while the ignition deviceis in the turn-on state, from at least one of switching to a turn-offstate and re-booting.
 7. Method of claim 1, further comprising providingthe voltage upscaling device in the user terminal (7).
 8. Method ofclaim 1, the boosting comprising boosting a reduced voltage level ofabout 2 to 4 V to a boosted voltage level of about 10 to 12 V.
 9. Methodof claim 1, wherein the providing comprises providing the user terminalin a tractor (1) of the agricultural machine, the tractor (1) trailingor carrying an implement (2), wherein at least some of the functionalelements (10 b) are provided on the implement (2).
 10. An agriculturalmachine, comprising a control system (3); a user terminal (7) providedin the control system (3); a power supply (13) connected to the userterminal (7) through a supply line; a voltage upscaling device connectedto the supply line; functional control elements (10 a; 10 b); and acontrol bus (6) provided in the control system (3) and configured totransmit control signals from the user terminal (7) to the functionalelements (10 a; 10 b); wherein the user control system (3) is configuredto operate the user terminal (7) according to a method of claim 1.